Method of making steam iron



Oct. 26, 1965 R- L. SWANKE METHOD OF MAKING STEAM IRON 2 Sheets-Sheet 1 Original Filed June 19, 1962 74 60 3 may 50 FIGJ zzvmvrozz ROY L. SWANKE ATTORNEYS Oct. 26, 1965 R. L. SWANKE 3,213,534

METHOD OF MAKING STEAM IRON Original Filed June 19, 1962 2 Sheets-Sheet 2 INVENTOR. ROY L. SWANNZ ATTO RNEYS United States Patent 3,213,534 METHOD OF MAKING STEAM IRON Roy L. Swanke, Southington, Conn., assignor, by mesne assignments, to General Electric Company, Bridgeport, Conn., a corporation of New York Original application June 19, 1962, Ser. No. 203,509, now Patent No. 3,165,844, dated Jan. 19, 1965. Divided and this application Jan. 23, 1964, Ser. No. 339,761

2 Claims. (Cl. 29-529) This invention generally relates to electric irons and is more particularly directed to a method of making an improved electric steam iron of the flash chamber type.

One of the objects of the present invention is the provision of a steam iron of the type above described having improved heat distribution and transfer characteristics and which will effectively generate steam at relatively low sole plate temperatures.

A further object of the present invention is the provision of such an iron which will emit steam substantially throughout the full length of its sole plate and wherein the emission of condensed or unvaporized water, often termed spitting will be greatly minimized.

A still further object of the present invention is the provision of such a steam iron that will attain the above objects in a compact structure that is economical to manufacture, easy to assemble and that will be extremely durable over long periods of use.

The main object of this invention is the provision of an improved method of making a sole plate having the characteristics described.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

This application is a division of my copending application Serial No. 203,509, filed June 19, 1962, for Steam Iron, now Patent No. 3,165,844.

In the drawings:

FIG. 1 is a cross section view of an electric steam iron embodying the present invention;-

FIG. 2 is a plan view of a sole plate constructed in accordance with the present invention;

FIG. 3 is a cross section view taken along lines 3-3 of FIG. '2;

'FIG. 4 is a fragmentary crosssectional view taken generally along lines 44 of FIG. 2;

FIG. 5 is a perspective view of a heating element and a tube which are incorporated in the sole plate of the present invention and which are shown with a fragment of a mold utilized in making the sole plate; and

FIG. 6 is a cross-sectional view of the sole plate shown in its mold.

Referring to the drawings in detail, FIG. 1 shows a steam iron embodying the present invention including a sole plate generally designated 4 and an overlying shell 6 attached at its rear to the sole plate by means of screw 8, and having a handle 10 and a rear compartment 12 apertured at 14 for receiving a conventional electrical cord (not shown). A plate 18 is attached at opposite ends to the shell 6 by means of screws 20, 21 to define with the shell a water reservoir 22, which is suitably sealed and access to which, for supply purposes, is provided by a port 24 in the front end of the shell. The plate 18 is apertured to receive a sleeve 28 which extends into a boss 30 formed on the upper face of the sole plate as shown in FIG. 1.

In order to regulate the temperature of the sole plate 4, a suitable thermostat generally designated 32 is located below the reservoir 22 between the plate 18 and the sole plate 4 and positioned in a recess 35 (see FIG. 2). The rivet 34 of the thermostat is mounted directly on the upper face 7 of the sole plate 4 and is positively positioned by a raised rib or projection 36 integrally formed with the 3,213,534 Patented Oct. 26, 1965 "ice sole plate. The rivet 34 is clamped to the sole plate by an arm 38 having one end portion suitably attached to the rivet 34 and another end portion supported on bosses 40 and 42, respectively, of the sole plate 4. The rivet 34 and arm 38 are preferably formed of good heat-conducting material so as to supply sole plate heat to a suitable bimetallic element (not shown) that controls the position of contact arm 43.

Referring to FIG. 1, in order to set the thermostat for regulating the sole plate temperature in accordance with a preselected temperature, a control knob 44 having suitable indicia thereon is mounted on a ledge 46 of the shell and is keyed to one end of a shaft or connecting stem 48 that is rotatably supported in portion 49 of shell 6. The other end of the connecting stem 48 is threadably received in a boss 50 formed on the sole plate and is provided with a flared portion 52 that cooperates with an insulated extension on thermostat contact arm 53 to adjust the setting of the thermostat upon longitudinal movement of the stem 48 effected by rotating the control knob 44.

Referring to FIG. 2, a generally V-shaped heating element 60, preferably of the sheathed type, is embedded in the sole plate 4 with its bight 62 in the front portion of the sole plate and its legs 63, 64 extending along the sides and terminating in the rear portion of the sole plate. Terminals 66, 68 are provided at each of the leg extremities of the heating element which are raised to extend into compartment 12, and are adapted to be respectively connected to the thermostat and one of the electrical cord lines in the usual manner.

In accordance with the present invention, a steam-generating or flash chamber is embedded in the sole plate 4 in good heat-exchange relationship with the heating element 60, and in the illustrated embodiment comprises a tube 70 preferably continuous and formed from copper and being configured to describe a generally V-shaped structure of double-legged construction best shown in FIG. 5. The extremities 72, 74 of the tube 70 are located forward of the bight 62 of the heating element 60 and are crimped closed while the body of the tube is formed to provide outer legs 76, 77 which extend along and contact the outer side of the heating element 60, and inner legs 78, 79 which extend along and contact the inner side of the heating element 60. The bight portion 80 joining inner legs 78, 79 of the tube 70 is disposed just rear- Wardly of and in contact with bight portion 62 of the heating element 60 while the outer legs 76, 77 of the tube 70 respectively meet the inner legs 78, 79 thereof at bights 81, 82 which curve around and preferably contact the leg extremity portions of the heating element 60 below the raised terminals 66, 68.

Referring to FIG. 1, water from reservoir 22 is admitted into the tube 70 for generating steam through supply port 85 provided therein at the bight 80, which port 85 is in communication with a valve passage 86 formed by the sleeve 28. A suitable valve 88 for controlling flow from the reservoir 22 into the tube 70 is provided in the front portion of the reservoir and includes a valve head 90 positioned in valve passage 86 and a valve stem 92 biased downwardly by a spring 94 to seat the valve head 90 on a seat 96 provided in the sleeve 28, to thereby cut off communication between the reservoir 22 and supply port 85 of the tube 70. Actuation of the valve stem 92 to unseat the valve head 90 for supplying water into the steam-generating tube 70 is accomplished by a suitable cam means provided on the ledge 46 and a valve stem retaining member 98 which cooperate to raise the stem in the desired knob position.

Discharge of the steam generated in the tube 70 is accomplished by the provision of a plurality of passages 83 provided in the sole plate at spaced points along the outer legs 76, 77 of the tube 70, each passage having one end in respective registry with one of the ports 71 which are provided in the tube 70 and the other end opening into the ironing face of the sole plate in flared fashion. The steam-emission passages 83 extend throughout the outer legs 76, 77 of the tube 70 so as to provide a wide distribution of steam from the sole plate during steam ironing. Additionally, the ports 71 of tube 70 open into the tube at locations spaced from the bottom of the tube as shown in FIG. 3 so as to provide minor water traps as will be subsequently described in greater detail.

In order to minimize the spitting of unvaporized or condensed water out of the sole plate, trap means for collecting such water in the tube 70 are provided. In the illustrated embodiment, a major water trap is provided in inner legs 78, 79 of the tube 70 by forming the bights 81, 82 of the tube 70 so as to lie in an elevated plane with respect to the remainder of the tube 70 as shown in FIGS. 1 and 5. Minor water traps, as stated above, are also provided and are formed in the outer legs 76, 77 by the provision of a series of transversely extending ridges 84, formed in the outer legs of tube 70 -with each ridge located between a pair of steam-emission passages 83 (as shown in FIGS. 2 and 4).

From the foregoing description, it is seen that the improved sole plate construction provides a steam distribution path that extends throughout substantially the whole periphery .of the sole plate in good heat-conducting relationship with the heating element. Additionally, an extended closed steam path from the point of water admission to the first position of steam emission is provided, which path is directly heated by the heating element to insure effective generation of steam.

In accordance with the method of the invention, the sole plate 4 whose body is preferably formed from an aluminum alloy or the like is preferably made by molding the aluminum alloy around the heating element 60 and the tube 70 to form a composite structure. In this process, the heating element 60 and the tube 70 are attached together in the desired manner and placed in the mold, the base 101 of the mold being shown in FIG. 5. The position of the heating element 60 and tube 70 when placed in the mold is positively located by a plurality of core pegs 100 equal in number and general arrangement to that of the steam-emission passages 83 as shown in FIG. 5. The pegs which are suitably supported in the base of the mold 101 are each provided with a tapered extremity 102 extending into the mold, and whose inner surface 103 is adapted to contact the outer surface of the tube 70 (as shown in FIGS. 5 and 6) through which a port 71 is to be formed. After the heating element 60 and tube 70 are properly located in the mold by the pegs 100, the sole plate body is cast into the form shown in FIG. 6. The pegs 100 are then removed from the sole 4 plate casting to provide passages 83, and the tube outlet ports 71 are then formed by placing an aperture-forming tool, such as a drill, in the passages 83 and forming the ports 71 in the side of the tube 70.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure and method above described will become readily apparent without departure from the spirt and scope of the invention, the scope of which is defined in the appended claims.

What is claimed is:

1. A method of making a steam iron sole plate having embedded therein a heating element and a tube forming a steam-generating chamber, and a plurality of steamemission passages opening into the tube at outlet ports therein, the steps comprising, attaching the heating'element and the tube together and placing them in a sole plate mold, using core pins in the mold at locations where the steam-emission passages are to be formed and with the end portions of the core pins contacting spaced portions of the tube, casting the sole plate around the heating element, tube and core pins, withdrawing the core pins to form the steam-emission passages, and inserting an aperture-forming tool in said passages and forming apertures in the tube at said portions to provide outlet ports in the tube in communication with the steam-emission passages.

2. A method of making a steam iron sole plate having embedded therein a heating element and a tube forming a steam-generating chamber, and a plurality of steamemission passages opening into the tube at outlet ports therein, the steps comprising, attaching the heating element and tube together so as to be in heat-exchange relationship with each other, placing the heating element and tube in a sole plate mold and positively locating the heating element and tube therein by the use of a plurality of core pins positioned in the mold at locations where the steam-emission passages are to be formed and with the ends of the core pins contacting spaced portions of the tube whereat the tube outlet ports are to be formed, casting the sole plate around the heating element, tube and core pins, withdrawing the core pins to form the steam-emission passages, and inserting an aperture-forming tool in said passages and forming apertures in the tube at said portions thereof to provide outlet ports in communication with the steam-emission passages.

References Cited by the Examiner UNITED STATES PATENTS 1,072,257 9/13 Pollock 3893 X 2,353,604 7/44 Waring et al.

3,028,666 4/62 Osbrink 29 527 3,118,225 1/64 McAndrews 22-203 X WHITMORE A. WILTZ, Primary Examiner. 

1. A METHOD OF MAKING A STEAM IRON SOLE PLATE HAVING EMBEDDED THEREIN A HEATING ELEMENT AND A TUBE FORMING A STEAM-GENERATING CHAMBER, AND A PLURALITY OF STEAMEMISSION PASSAGES OPENING INTO THE TUBE AT OUTLET PORTS THEREIN, THE STEPS COMPRISING, ATTACHING THE HEATING ELEMENT AND THE TUBE TOGETHER AND PLACING THEM IN A SOLE PLATE MOLD, USING CORE PINS IN THE MOLD AT LOCATIONS WHERE THE STEAM-EMISSION PASSAGES ARE TO BE FORMED AND WITH THE END PORTIONS OF THE CORE PINS CONTACTING SPACED PORTIONS OF THE TUBE, CASTING THE SOLE PLATE AROUND THE HEATING ELEMENT, TUBE AND CORE PINS, WITHDRAWING THE CORE PINS TO FORM THE STEAM-EMISSION PASSAGES, AND INSERTING AN APERTURE-FORMING TOOL IN SAID PASSAGES AND FORMING APERTURES IN THE TUBE AT SAID PORTIONS TO PROVIDE OUTLET PORTS IN THE TUBE IN COMMUNICATION WITH THE STEAM-EMISSION PASSAGES. 